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Where “START” and “END” are the set values in ppm, the “Step Time” is 1.25ms, Δt in seconds
and the “Step Size” will come out as ppm value.
In between the 1.25ms step time, a second HW interpolation counter will update the set value
for every 78μs (fast ramp times) to about 78μs (slow ramp times).
Starting the ramp is done with the trig command “TS (stack no.)”.
If synchronization to an external event is required, it is possible to arm the ramp sequence first
with the synchronization command:
“SYNC (stack no.), [trigger delay]”.
A hardware signal on the trigger input X9, pins 1 & 2 (10 to 24V) or a TS command will start
the sequence. If a trig delay is entered, the sequence will first start after the delay time has
elapsed.
If more power supplies require synchronization, one of them must be designated to be master.
Connecting the master trig output X9, pins 3 & 4 to the other supplies´ trig input will start the
other supplies when the master is triggered. A maximum skew of 5μs between the supplies may
be expected (an external 15V auxiliary supply is needed since the trig output is an open
collector and the trig input is an optocoupler input).
3.3.5.2. Equal time slot ramp profile method
With the ”equal time slot method”, it is possible to download up to 1000 current set values and
a single time slot value for use with all set values. Only one stack is available.
This profile method is especially applicable for faster and more accurate curve-fitting profiles
such as a function generator.
To use the equal time slot method, at least the following steps must be performed:
Clear and set the stack “RAMPSET [parameter]”
Program the stack “R [parameter]”
Start the stack “RAMP [parameter]”
Read the status of the running stack “RAMP"
NOTE
One difference in the value parameters setting as opposed to the “Arbitrary point
method” is, that all values must be given as a floating point number scaled to
“1.000000". This means 1.25ms must be entered as 0.00125 and 19.54% output current
as 0.1954.
Please refer to the Software manual about Ramp Profile Commands for full instructions.
The figure below shows an example of one ramp profile stack (note: not all 1000 points need to
be programmed, empty entries will be ignored.)
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